It has been proposed previously to provide many types of air-bag which incorporate a mounting region or mounting tabs in order to mount the air-bag in position. One particular form of air-bag of this type is the so-called inflatable curtain. An air-bag of this general type is disclosed in GB 2297950A.
FIG. 1 illustrates a part of an inflatable curtain air-bag. The air-bag has an inflatable region 1 which has a generally linear upper edge 2. The inflatable region 1 is formed by two superimposed layers of fabric which are secured together at selected regions. In some cases, the air-bag is formed using a one-piece weaving process (as disclosed in WO90/09295), in which selected regions of the two layers of fabric are co-woven to form a single layer of fabric. In the part of the air-bag shown in FIG. 1, the two layers of fabric of the inflatable region are woven together in an area 3 to form a non-inflatable area, and are also woven together in regions 4, 5 which form seams separating individual inflatable cells 6, 7. A gas supply duct 8 is defined which extends adjacent to the upper edge 2 of the air-bag, as is conventional. The gas supply duct is in fluid communication with the inflatable cells 6, 7.
The upper edge 2 of the air-bag is provided with a plurality of protruding mounting tabs 9, each of which is provided with an aperture 10. The mounting tabs may be used to mount the air-bag in position within the roof lining of a motor vehicle, above the side windows of the vehicle.
On inflation of the air-bag, where mounted in position in a motor vehicle by the mounting tabs 9, a very substantial force is applied to the mounting tabs. In order to minimise the risk of the tabs tearing under such forces, it has been proposed to reinforce the mounting tabs by providing extra material, or by folding the material over on itself in order to increase the thickness of the mounting tabs, or even by providing additional reinforcing sewing. All of these expedients, however, increase the weight and cost of the air-bag.
In other forms of air-bag, the mount may be a ring-shaped mount surrounding a large aperture that receives a gas generator. The mount typically has apertures to receive bolts on a flange of the gas generator. Again, the mount is typically reinforced by making the mount of increased thickness, or by sewing on an extra layer of reinforcing fabric.